Question

A copper rod of diameter $1cm$ and length $8cm$ is drawn into a wire of length $18cm$ of uniform thickness. Find the thickness of the wire.

Answer 1

copper rod diameter = 1 cm

length of rod = 8 cm

- wire length = 18 cm

$\to$ thickness of wire = (9)

$\to$ volume of copper rod = volume of wire

$\therefore \pi r^2.h=\pi R^2.H$

$\therefore \pi \times (0.5{)}^2\times 8=\pi \times R^2\times 18$

$\therefore R^2=\frac{(0.5{)}^2\times 8}{18}=0.111$

$\therefore R=0.333cm$

$\to$ thickness of wire $=d=2R=2\times 0.33=0.666cm$